An important aspect of any retail industry is to properly display and update prices associated with every product in the store. Price displays are often placed in clear plastic protective covers which connect to the edge of shelving underneath the product for which the price tag is associated. Thus, in order to change the price display of a particular item, an employee would have to print out a new paper price display and physically go to the location of the product in the store to switch the old price display held in the plastic cover with the new one. Additionally, someone would have to be responsible for ensuring that the price was simultaneously updated in the store computer so customers are charged the correct price for every item at the checkout counters.
Given the cumbersome tasks involved with updating and verifying the accuracy of the price tags associated with every product in a store, there has recently been developed an optical price tag. The optical price tag is a battery operated device which uses a liquid crystal display (LCD) to display pricing information and/or other information related to the product with which it is associated. Because the price tags can receive optical transmissions, automatic price updates can occur through ceiling mounted optical transceivers which communicate with the optical price tags. The ceiling mounted optical transceivers are connected to the store's host computer. With this technology, it is no longer necessary for store employees to spend many hours physically updating pricing information. Furthermore, since the store's host computer is used to initiate the price change, the price stored in the host computer will automatically match the price displayed on the shopping floor.
These optical shelf tags typically employ batteries as power sources since the batteries provide for easy installation of the shelf tags and make them easier to relocate as opposed to shelf tags which are hardwired for power and/or communications. However, one practical drawback with using a remote power supply such as a battery is that the batteries need to be replaced. Once the batteries are drained, the shelf tag becomes inoperative until it is replaced with another battery. Although current battery technology may provide for several useful years of life for powering the optical shelf tag before needing replacement, there is a continuing need for improvement of prolonged battery life so that the batteries will need replacing less often, and thus reducing the amount of extra time needed for maintenance of the optical shelf tags.
Furthermore, many conventional optical shelf tags employ LCD displays which can sometimes be difficult to read under certain ambient light conditions. For example, if it is very bright around the shelf tag, the display may be difficult to read. Likewise, if lighting conditions are dim, the shelf tag display may be difficult to read.
Accordingly, in view of the above, there is a strong need in the art for an electronic shelf tag which can vary its power state in accordance with surrounding ambient light in order to conserve power. Furthermore, there is a need for an electronic shelf tag which can vary its display characteristics according to ambient lighting conditions so as to optimize viewability of its display.